Apparatus for removing rock from unscreened sugar cane juice

ABSTRACT

AN APPARATUS FOR REMOVING ROCK FROM RAW AND UNSCREENED SUGAR CANE JUICE WHICH UTILIZES A DAM ACROSS THE BOTTOM OF A TROUGH CARRYING THE JUICE STREAM. THE DAM DIRECTS THE ROCK TO A VERTICAL TRAP FROM WHICH THE ROCK IS REMOVED BY A CONVEYOR.

0ct.'l7, 1972 K. E. STEPPE ETAL 3,698,949

APPARATUS FOR BEMOYING ROCK FROM UNSCREENED SUGAR CANE JUICE Filed Nov. 27, 1970 INVENTOR.

Amman-"o L-WEBRQ Ara.

United States Patent 3,698,949 APPARATUS FOR REMOVING ROCK FROM UNSCREENED SUGAR CANE JUICE Kenneth E. Steppe, Lambertville, Mich., and Alfred L.

Webre, Jr., Marsh Harbour, Bahamas, assignors to Owens-Illinois, Inc.

Filed Nov. 27, 1970, Ser. No. 93,029 Int. Cl. C13d 3/.00

US. Cl. 127-9 3 Claims ABSTRACT OF THE DISCLOSURE An apparatus for removing rock from raw and unscreened sugar cane juice which utilizes a dam across the bottom of a trough carrying the juice stream. The dam directs the rock to a vertical trap from which the rock is removed by a conveyor.

BACKGROUND OF THE INVENTION stalks and are fed into the raw sugar factory. The sugar cane stalks are initially fed into a grinding mill wherein a plurality of heavy rollers, usually three, cooperate to crush and squeeze the cane to thereby separate the juices from the cane itself. This juice and a small amount of residual cane, termed cush-cush, falls through the bottom of the grinding mill and is removed by means of a juice trough. The juice and residual cane are then conducted to and passed over a series of screens which remove the residual cane or cush-cush from the juice and the cush-cush is then recycled for further processing through the grinding mill. The resulting juice is then in a form suitable for the raw sugar factory. It has been found, however, that small size rocks which are fed into the grinding mill with the sugar cane frequently pass through the grinding mill with the juice and cush-cush. When this combination reaches the aforementioned screening section, part of these rocks are removed by the screen and recycled with the cush-cush. Unfortunately, with each successive pass through the grinding mill and screening process, the rocks become ground into fine particles, such as sand, and eventually escape into the raw sugar factory with the resulting sugar cane juice. The removal of these rock or sand particles from the sugar cane juice in the refinery is an extremely expensive procedure and has been a considerable problem in the sugar cane processing industry for some time.

SUMMARY OF THE INVENTION It is, therefore, an object of this invention to provide a unique process and apparatus for removing rock from the sugar cane juice before it is screened and delivered to the refinery. The apparatus of this invention comprises a dam and rock removal trap positioned in the juice trough which connects the grinding mill and the screening apparatus. The rocks that pass through the grinding kmill with the juice and residual cane are removed by the dam and fall through a vertical trap onto a slat conveyor.

Other objects, features, and advantages of this invention will become obvious to those skilled in the art to which it pertains upon reference to the following detailed description and the drawing illustrating a preferred embodiment.

In the drawing:

The figure is a schematic perspective view with parts broken away in section of a portion of a sugar cane proc- 3,698,949 Patented Oct. 17, 1972 essing factory incorporating the unique rock removal apparatus of this invention.

DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT In the apparatus shown in the figure, sugar cane stalks are deposited on a large moving conveyor 10 for delivery to a grinding mill section 12. As mentioned previously, the sugar cane stalks which are deposited on the conveyor 10 are accompanied by a considerable quantity of rocks which become entangled with the cane stalks during harvesting. The grinding mill 12 has a plurality of rollers (not shown) which are positioned to grind and squeeze the sugar cane stalks so as to remove the juice therefrom. Although not shown here in detail, a typical grinding mill includes three rollers positioned in triangular relationship which grind the sugar cane stalks so as to remove the sugar cane juice which drops into a trough at the bottom of the grinding mill. Typically, small amounts of residual cane or cush-cush and small rocks also pass through the grinding mill 12 and are removed with the sugar cane uice.

A juice trough 14 is provided to direct the combination sugar cane juice, cush-cush, and rocks removed in the grinding mill 12 towards a screening section (not shown). In standard sugar cane factories, the juice trough 14 is a continuous trough to direct the juice, residual cane, and rocks directly from the grinding mill 12 to the screening section.

However, the unique apparatus of this invention includes a rock removal system, generally indicated by the numeral 16, to remove all rocks from the juice trough 14 before the juice and cush-cush reach the screening section. The rock removal apparatus features a low darn 18 which extends across the full width of the lower portion of the trough 14. A vertical rock removal trap 20 having an opening 22 in the bottom of the trough 14 is positioned slightly in advance of the dam 18 to facilitate removal of the rocks 24 by dam 18. The vertical rock removal trap 20 extends downwardly into a closed conveyor housing 26. Positioned within the conveyor housing 26 is a slat type conveyor, generally indicated by the numeral 28, which includes a plurality of slats 30 mounted between and for travel with a pair of moving chains 32. The chains 32 are caused to rotate about a pair of pulleys 34 and 36. The pulley 34 is driven by means of a suitable motor 38 and drive belt 40 mounted on the outside of conveyor housing 26. It should be noted that the conveyor housing 26 is oriented in an angular direction so that its outlet end 42 is considerably higher than its inlet end 44 and is positioned above the level of the juice within juice trough 14. The outlet end 42 of the conveyor housingv 26 includes a vertical chute 46 which opens into a rock removal container 48.

In operation, the sugar cane juice, cush-cush, and rocks 24 are separated from the sugar cane stalks in the grinding mill 12 and are forced to flow along the juice trough 14 in the direction indicated by the arrows. When the combined flow reaches the vertical dam 18, the rocks 24 are prevented from going further by means of the dam 18 and forced to fall through the opening 22 in the bottom of the juice trough 14 and are directed by the vertical rock removal trap 20 onto the conveyor housing 26. The rocks 24 actually rest on the bottom surface of the conveyor housing 26 and are moved therealong by means of the slats 30 of the slat or drag conveyor 28. The rocks 24 are then moved upwardly along the conveyor housing 26 passing out of the fluid level, indicated by numeral 50, and fall through vertical chute 46 into rock removal container 48. A continuous flow of combined sugar cane juice is caused to flow backward (i.e., to the left in the figure) from the direction of rock flow within the conveyor housing 26 and upward through the vertical trap 20. This counter-flow of juice prevents the residual cane or cushcush within the juice trough 14 from falling through the vertical trap 20. Having the rocks 24 eliminated therefrom, the remaining sugar cane juice and cush-cush continues on through the juice trough toward the screening section (not shown) where the cush-cush is screened from the juice thereby preparing the juice for delivery to the sugar refinery. This cush-cush removed in the screening section is then recycled back to the conveyor and reprocessed through the grinding mill 12.

Thus, it can be seen from the preceding description that the rock removal apparatus of this invention, although relatively simple in structure, is adapted to effectively remove the unwanted rocks from unscreened sugar cane juice prior to its delivery to a raw sugar factory. The removal of the rocks by the apparatus of this invention completely eliminates the necessity of removing the ground up rocks or sand particles which frequently are found in sugar cane juice as it enters a raw sugar factory. The rock removal apparatus of this invention has been found to be so successful that the necessity of utilizing expensive sand and rock particle removal processes in the sugar factory has been completely eliminated. In addition, the removal of the rocks from the sugar cane juice before it reaches the screening section has resulted in considerably less wear and tear on the screening components of the screening section.

We claim:

1. Apparatus for removing undesirable solid objects from a flowing stream of raw, unscreened sugar cane juice comprising, in combination:

trough means for receiving said lflowing stream of raw,

unscreened sugar cane juice, said trough means having at least one opening formed in the lower surface thereof;

a dam member positioned within and on the lower surface of said trough means at a location downstream of said opening in the lower surface of said trough means for blocking the flow of said solid objects with said raw, unscreened sugar cane juice through said trough means, so that said solid objects fall into said opening in the lower surface of said trough means;

trap means connected to said opening in the lower surface of said trough means for removing said solid objects from said trough means;

and closed conveyor means positioned to receive said solid objects from said trap means and to remove said solid objects from said raw, unscreened sugar cane juice.

2. Apparatus for removing undesirable solid objects from a flowing stream of raw, unscreened sugar cane juice comprising, in combination:

trough means for receiving said rflowing stream of raw,

unscreened sugar cane juice, said trough means having at least one opening formed in the lower surface thereof;

dam means positioned within said trough means downstream of said opening in the lower surface of said trough means for blocking the flow of said solid objects with said raw, unscreened sugar cane juice through said trough means, so that said solid objects fall into said opening in the lower surface of said trough means;

trap means connected to said opening in the lower surface of said trough means for removing said solid objects from said trough means;

and closed conveyor means positioned to receive said solid objects from said trap means and to remove said solid objects from said raw, unscreened sugar cane juice, said closed conveyor means includes a housing having a lower object-receiw'ng end connected to said trap means and positioned below the level of said raw, unscreened sugar cane juice within said trough means and an upper object-discharging end which is positioned above the level of said raw, unscreened sugar cane juice in said trough means, a slat-type revolving conveyor positioned within said housing for moving said solid objects received from said trap means from the lower object-receiving end of said housing to the upper object-discharging end of said housing, and a solid object discharge chute positioned at the upper object-discharging end of said housing for removing said solid objects from said slat-type conveyor.

3. Apparatus as set forth in claim 2 wherein said dam means positioned within said trough means comprises a substantially rectangular flat plate having a width equal to the width of said trough means and a height less than the height of said trough means.

References Cited UNITED STATES PATENTS 1,871,583 8/1932 Burnside 209158 3,544,458 12/1970 Sato 210- FOREIGN PATENTS 987,908 3/ 1965 Great Britain. 1,061,709 7/ 1959 Germany.

MORRIS O. WOLK, Primary Examiner 0 s. MARANTZ, Assistant Examiner U.S. Cl. X.R. 

